The present invention pertains to the remote control of a vehicle, and in particular, to a control system and method which allows for manual, autonomous and tele-operation of underground mining vehicle.
Mine environments are inherently dangerous areas due to the instability of underground ore bodies. Around the world, there are numerous instances of ore bodies collapsing on mining vehicle operators. Mines are also very hot with high levels of dust. To accommodate the mining vehicle operators, air conditioned cabs are added to mining vehicles and an underground ventilation system is built inside the mine. However, in mining, for economic reasons, it is always desirable to keep infrastructure costs to a minimum.
Accordingly, there is a migration towards remote mining in which mining vehicles are controlled by an operator from a safe location. First generation remote mining schemes required the operator to have an open line of sight to the mining vehicle (i.e. be in the vicinity of the mining vehicle), however, this still placed the operator in the mine. In addition, the operator could only operate one mining vehicle at a time. Second generation remote mining schemes placed the operator, now referred to as a tele-operator, In a remote tele-operator station which may be below or above ground. In this remote mining scheme, the tele-operator has visual information about the mining vehicle, displayed l uia screen, to allow the tele-operator to visually monitor the mining vehicie""s activities and environment.
Remote mining greatly increases the safety of underground mining since the mining vehicle operator is removed from areas where there are collapsing ore bodies. There is also an increase, in worker productivity and equipment utilization since the travel time needed to get the mining vehicle operator to the mining vehicle, which can be up to 1.5 hours, is eliminated. In addition, remote mining results in lower infrastructure cost.
In mining there is also a movement towards autonomous operation of mining vehicles since some mining operations are labor intensive and repetitive. Accordingly, the autonomous operation of mining vehicles has potential cost and labor savings. Furthermore, autonomous operation of mining vehicles allows the tele-operator to operate more than one mining vehicle since the tele-operator is only needed for specific operations such as when a Load Haul Dump (LHD) vehicle is loading or dumping. The cost of having an individual tele-operator for each mining vehicle is therefore avoided. Another benefit in autonomous mining vehicle operation is that tramming will be more consistent and accurate which is useful in mining areas where there are tight clearances. This is advantageous since mining vehicle operators routinely damage mining vehicles to the point where some mining vehicles last for only three months.
To facilitate the autonomous operation and tele-operation of a mining vehicle, a conventionally designed mining vehicle has the necessary control and comunications system added to it. This then allows for manual control of the mining vehicle which is important since autonomous operation is implemented only along high traffic routes such as from a work face to a locaton for dumping ore. Furthermore, there are occasions when a mining vehicle must be manually driven such as when the mining vehicle is taken to a service ceilbe for routine maintenance or refuelling.
Autonomous vehicles have already been used in a variety or industrial settings. However, the control, system used in an industrial setting cannot be readily applied to a mining vehicle. This is because a mining invironment is much harsher than a conventional factory environment. Thus, when control systems designed for industrial factory environments are applied to a mining vehicle, the result is poor systems reliability with failures often occurring due to mining environmental factors such as temperature, acidity, vibrations, etc. There is also constant wear and tear on these control systems since the enclosure and system connections are not air tight which allows moist air to enter controllers and damage internal electronics.
Prior art control systemic were based on Programmable Logic Controllers (PLCs) with separate commercially available modules being used to provide radio communication and image processing. This control system was expensive since the cost of a PLC and a video processor alone was significant. This control system was also hard to mass produce because the various subsystems rollowed different equipment practices and were not designed to operator together in a single package. This resulted in increased hardware complexity, complex wiring and a large system enclosure. PLC-based control systems also used a rock in which the I/O modules were stacked, which resulted in complex wiring and a control system that had to be cutomized for a particular vehicle. This design made system maintenance troubleshooting and transferal of the control system from one mining vehicle to another difficult.
The vision system of the prior art mining vehicle control systems utilized scanning lasers for guidance. However, the guidance system is inherently fragile since the guidance scanning lasers, mounted on top of the mining vehicle, quite often get damaged or knocked off due to overhanging ventilation pipes and the like or rock falls which occur when the mining vehicle is digging. Typically a mining vehicle can lose a couple of guidance scanning lasers per month which can be very expensive since a guidance scanning laser costs approximately 10,000 dollars Canadian.
A PLC-based control system is also difficult to troubleshoot since control system information is stored in a number of registers implemented in memory. To troubleshoot a PLC-based control system, one needs to access the correct registers. Thus, there is a need for a control system which can provide diagnostic information. Furthermore, there is a need for powerful on-line program editing and debugging tools and the ability to download programs to support control systems from a remote location. Remote maintenance support is important since mining vehicles can be operating in remote parts of the world.
Accordingly, there is a need for a robust control system which can withstand the harsh mining environment. Furthermore, the control system should have an application specific design which will result in a smaller unit, with simplified connections to allow for easy maintenance. In addition, the control system should allow for long distance maintenance support.
The present invention provides a control unit, for mounting with a machine for enabling control thereof from a tele-operator station via a communications channel. The control unit comprises a control input for receiving control signals from the tele-operator station and a digital processing means connected to the control input for processing the control signals and generating commands. The control unit further includes a control output for providing the commands to the machine and a second input connected to the digital processing means for receiving data from sensors on the machine indicative of the location and status of the machine. The control unit also has a data output for providing visual data to the tele-operator station. The control unit is adapted to operably switch between a manual mode in which the machine is controlled locally by controls on the machine, an autonomous mode in which the machine is controlled by data received through the second input, and a tele-operation mode in which the machine is controlled remotely by the control signals based at least in part on the visual data.
In another aspect, the present invention provides a control unit, for mounting on a machine, for enabling control thereof from a tele-operator station via a communications channel. The control unit comprises a control input for receiving control signals from the tele-operator station, and a digital processing means connected to the control input for processing the signals and generating commands. The digital processing means comprises a main processor and a supervisory processor connected to the main processor for monitoring the main processor to ensure safe operation of the machine. The control unit further includes a control output for providing the commands to the machine, and, a second input for receiving data from sensors on the machine indicative of the status of the machine. The control unit also has an enclosure that is adapted to prevent ingress of contaminants. The digital processing means is located in the enclosure.
In another aspect, the present invention provides a method of controlling a machine from a remote tele-operator station via a communications channel, the method comprising:
(a) providing the machine with a control unit capable of enabling at least two modes of operation selected from the group consisting of manual operation, autonomous operation, and tele-operation;
(b) selecting a desired mode of operation from the at least two modes of operation;
(c) operating the machine in the desired mode of operation; and,
(d) receiving visual data from the control unit at the tele-operator station enabling activity of the machine to be monitored in at least one of the two modes of operation.
A control unit, for mounting on a machine, for enabling control thereof from a tele-operator station via a communications channel, the control unit comprising:
(1) a control input for receiving control signals from the tele-operator station;
(2) a digital processing means connected to the control input for processing the signals and generating commands,
(3) a control output for providing the commands to the machine; and,
(4) a second input for receiving data from sensors on the machine indicative of the status of the machine, wherein, the digital processing means comprises a main processor and a supervisory processor connected to the main processor for monitoring the main processor to ensure safe operation of the machine, and wherein at least one of: the main processor provides periodic status signals to the supervisory processor to indicate correct operation of the main processor; and the supervisory processor randomly queries the status of the main processor, to ensure correct operation of the main processor.
(3) guiding the vehicle along said selected path. The autonomous mode of operation further includes, providing for the vehicle to travel along a plurality of slotted paths, and for each path, first causing the vehicle to traverse a path in the tele-operation mode and simultaneously recording operator inputs, and, in subsequent autonomous mode operation, providing for the control unit to use the operator inputs for travelling each path.